means that it consists merely in the changes which it brings about in others; therefore itself and in itself it is nothing at all. Only of matter is it true, as I have said in the text, and worked out in the essay on the principle of sufficient reason, at the end of § 21, that its being consists in its action, that it is through and through only causality, thus is itself causality objectively regarded; hence, however, it is also nothing in itself ((
Greek characters), materia mendacium verax), but as an ingredient in the perceived object, is a mere abstraction, which for itself alone can be given in no experience. It will be fully considered later on in a chapter of its own. But the perceived object must be something in itself, and not merely something for others. For otherwise it would be altogether merely idea, and we would have an absolute idealism, which would ultimately become theoretical egoism., with which all reality disappears and the world becomes a mere subjective phantasm. If, however, without further question, we stop altogether at the world as idea, then certainly it is all one whether I explain objects as ideas in my head or as phenomena exhibiting themselves in time and space; for time and space themselves exist only in my head. In this sense, then, an identity of the ideal and the real might always be affirmed; only, after Kant, this would not be saying anything new. Besides this, however, the nature of things and of the phenomenal world would clearly not be thereby exhausted; but with it we would always remain still upon the ideal side. The real side must be something toto genere different from the world as idea, it must be that which things are in themselves; and it is this entire diversity between the ideal and the real which Kant has proved in the most thorough manner.
Locke had denied to the senses the knowledge of things as they are in themselves; but Kant denied this also to the perceiving understanding, under which name I here comprehend what he calls the pure sensibility, and, as it
